917
FXUS65 KGJT 310442
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
942 PM MST Thu Jan 30 2025

.KEY MESSAGES...

- Mild and dry conditions prevail through Friday, with
  temperatures 5-10 degrees above climatology.

- The next storm arrives Saturday and will bring measurable
  snowfall to our northern and central mountains through the
  weekend. Heaviest accumulations will be on the northern
  mountains.

- Unsettled weather with AR moisture is expected to continue
  through the week with lighter snowfall Monday and Tuesday,
  then heavier snows arriving Wednesday and Thursday that are
  expected to spread south to the San Juans.

&&

.SHORT TERM /THROUGH FRIDAY NIGHT/...
Issued at 233 PM MST Thu Jan 30 2025

Ahead of the Pacific system coming ashore this afternoon, high
pressure is in control for most of the CWA. Ample sunshine has
brought another round of mild temperatures to our low desert
valleys, with temperatures approaching 50 degrees again this
afternoon. Some lingering moisture on the backside of the departing
low has kept some low clouds over the southeast portion of the CWA
around Pagosa Springs, likely including a few snow flurries without
any appreciable accumulations. Clear and cold conditions will
descend upon the CWA tonight with our usual cold basins below zero
in the Upper Yampa Valley and the Gunnison area. Friday will bring
another round of mild conditions with the ridge moving overhead and
the next wave of unsettled weather on our doorstep by early Saturday
morning. Afternoon highs will trend 5-10 degrees over climatology.
Clouds will begin to invade the northwest corner of the CWA and
increase to the southeast through the evening. This is expected to
shut off radiational cooling and raise morning lows a touch
Saturday. The timing of cloud cover and efficient radiational cooling
make for a delicate temperature forecast. I still expect the
Gunnison Basin to see another subzero morning, while denser cloud
cover in the Yampa Basin is expected to keep temps above zero there.
Pacific moisture arrives by daybreak Saturday and perhaps brings a
flurry or two to the eastern Uintas and the Park Range. Much of this
moisture will probably get chewed up saturating the boundary layer,
with accumulating snow not expected until later Saturday.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 233 PM MST Thu Jan 30 2025

A series of Atmospheric Rivers (ARs) driving inland along the West
Coast will keep us on our toes through the long term. First up, this
weekend: Weak to moderate AR conditions drag a plume of moisture
across Northern California and Southern Oregon tonight/tomorrow. Its
remnant moisture, carried through nearly zonal flow is progged to
reach our northern ranges by Saturday morning. Due westerly winds
are not ideal for snow accumulation across the Uintas, though quite
conducive to generating snow across the Upper Yampa Basin corridor.
While the first AR starts to bring the Colorado Rocky Mountains
snow, a second and notably stronger AR makes landfall along northern
California. There are still some discrepancies with the placement of
this AR`s landfall between deterministic models, which leave
uncertainties with regard to how much moisture reaches eastern Utah
and western Colorado. The Elkheads, Park and Gore Ranges could see
continuous snowfall Saturday through Sunday; however, the southern
extent of the second AR will be a limiting factor in how much (if
any) snow falls across central to southern ranges. A northern shift
in our moisture source can greatly change snow totals over the
weekend. That being said, the Elkheads, Park to Gore Ranges may see
1 to 2 feet of snow Saturday morning through Sunday night.

In the wake of the second AR, winds aloft turn to the southwest as a
low pressure system slides south along the PacNW coast. Yet, another
AR, rounding the base of this low could return widespread
preciptation by mid week. However, moisture availability will rely
heavily on the southern extent of said low, and where the the AR
penetrates the interior west. Again, subtle changes in these
patterns may drastically change our snow forecast. So, I`ll hold off
from spitting out futuristic snow totals, for now.

Areas south of AR activity this weekend will continue to warm well
above normal for early February. Saturday highs start out roughly 10
degrees above normal, reaching 15 to 20 degrees above normal by
Mon/Tues. Those warm temperatures come at a price, however, in the
form of wind. Thus, expect gusty southwest winds early next week,
ahead of the PacNW low.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 941 PM MST Thu Jan 30 2025

VFR conditions will prevail for the next 24 hours. High clouds
will build in from the north tomorrow afternoon, but otherwise
skies will remain clear. Winds will be light and terrain driven.
Will keep an eye out for fog and low stratus development at KGUC
and KHDN overnight tonight. Such development could lead to
periods of MVFR to IFR until 15z at KHDN and GUC.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...None.
UT...None.

&&

$$

SHORT TERM...LTB
LONG TERM...ERW
AVIATION...TGJT